Dresden 2003 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

TT: Tiefe Temperaturen

TT 19: Supraleitung: Elektronenstruktur, Phononen, Tunneln, Ordnungsparameter II

TT 19.7: Vortrag

Donnerstag, 27. März 2003, 16:00–16:15, HSZ301

Electronic structure and superconductivity in MgB₂ and related systems — •H. Rosner¹, S.-L. Drechsler², S.V. Shulga², V.D.P. Servedio², G. Fuchs², K.-H. Müller², H. Rauf², P. Oppener², G. Behr², Y. Naidyuk³, K. Winzer⁴, O. Otani⁵, J.M. An⁶, W.E. Pickett⁶, and H. Eschrig² — ¹MPI CPfS Dresden — ²IFW Dresden — ³NAS Kharkiv, Ukraine — ⁴Univ. Göttingen — ⁵NIMS Tsukuba, Japan — ⁶UC Davis, USA

Combining extensive electronic structure and model calculations for normal and superconducting state properties with various experiments (specific heat, resistivity, susceptibility, de-Haas-van-Alphen oscillations, ARPES, point contacts and optics) we investigate the electronic structure and the electron phonon coupling λ in various diborides with focus on MgB₂, ZrB₂ and LiBC. Comparing dHvA and ARPES data with LDA calculations we conclude the high reliability of the latter for this class of compounds. Based on our calculations, we provide a clear microscopic picture for the rather different λ’s in agreement with the empirically determined values from thermodynamic and transport measurements. Our results allow a classification in strongly (MgB₂, LiBC) and weakly coupled systems (i.e. ZrB₂). Open problems are briefly discussed.